From d6a6734b6598e13a7ef1ab5f0b69fb27f485e4eb Mon Sep 17 00:00:00 2001
From: James Shubin <james@shubin.ca>
Date: Sat, 16 Mar 2024 00:35:33 -0400
Subject: [PATCH] lang: Plumb the ctx deeper into the lang API

---
 lang/gapi/gapi.go |  6 +++---
 lang/lang.go      |  4 ++--
 lang/lang_test.go | 14 +++++++-------
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lang/gapi/gapi.go b/lang/gapi/gapi.go
index 5f498aaa..bcfc48ca 100644
--- a/lang/gapi/gapi.go
+++ b/lang/gapi/gapi.go
@@ -427,7 +427,7 @@ func (obj *GAPI) Init(data *gapi.Data) error {
 }
 
 // LangInit is a wrapper around the lang Init method.
-func (obj *GAPI) LangInit() error {
+func (obj *GAPI) LangInit(ctx context.Context) error {
 	if obj.lang != nil {
 		return nil // already ran init, close first!
 	}
@@ -456,7 +456,7 @@ func (obj *GAPI) LangInit() error {
 			obj.data.Logf(Name+": "+format, v...)
 		},
 	}
-	if err := lang.Init(); err != nil {
+	if err := lang.Init(ctx); err != nil {
 		return errwrap.Wrapf(err, "can't init the lang")
 	}
 	obj.lang = lang // once we can't fail, store the struct...
@@ -553,7 +553,7 @@ func (obj *GAPI) Next() chan gapi.Next {
 				// run up to these three but fail on err
 				if e := obj.LangClose(); e != nil { // close any old lang
 					err = e // pass through the err
-				} else if e := obj.LangInit(); e != nil { // init the new one!
+				} else if e := obj.LangInit(context.TODO()); e != nil { // init the new one!
 					err = e // pass through the err
 
 					// Always run LangClose after LangInit
diff --git a/lang/lang.go b/lang/lang.go
index 7b37ece2..33a06436 100644
--- a/lang/lang.go
+++ b/lang/lang.go
@@ -99,7 +99,7 @@ type Lang struct {
 // NOTE: The trick is that we need to get the list of funcs to watch AND start
 // watching them, *before* we pull their values, that way we'll know if they
 // changed from the values we wanted.
-func (obj *Lang) Init() error {
+func (obj *Lang) Init(ctx context.Context) error {
 	if obj.Debug {
 		obj.Logf("input: %s", obj.Input)
 		tree, err := util.FsTree(obj.Fs, "/") // should look like gapi
@@ -232,7 +232,7 @@ func (obj *Lang) Init() error {
 		Debug:  obj.Debug,
 		Logf:   logf,
 	}
-	unifyErr := unifier.Unify(context.TODO())
+	unifyErr := unifier.Unify(ctx)
 	obj.Logf("type unification took: %s", time.Since(timing))
 	if unifyErr != nil {
 		return errwrap.Wrapf(unifyErr, "could not unify types")
diff --git a/lang/lang_test.go b/lang/lang_test.go
index 945db07d..f2ff9569 100644
--- a/lang/lang_test.go
+++ b/lang/lang_test.go
@@ -128,23 +128,23 @@ func runInterpret(t *testing.T, code string) (_ *pgraph.Graph, reterr error) {
 	}
 	logf("tree:\n%s", tree)
 
+	wg := &sync.WaitGroup{}
+	defer wg.Wait()
+
+	ctx, cancel := context.WithCancel(context.Background()) // TODO: get it from parent
+	defer cancel()
+
 	lang := &Lang{
 		Fs:    fs,
 		Input: "/" + interfaces.MetadataFilename, // start path in fs
 		Debug: testing.Verbose(),                 // set via the -test.v flag to `go test`
 		Logf:  logf,
 	}
-	if err := lang.Init(); err != nil {
+	if err := lang.Init(ctx); err != nil {
 		return nil, errwrap.Wrapf(err, "init failed")
 	}
 	defer lang.Cleanup()
 
-	wg := &sync.WaitGroup{}
-	defer wg.Wait()
-
-	ctx, cancel := context.WithCancel(context.Background()) // TODO: get it from parent
-	defer cancel()
-
 	wg.Add(1)
 	go func() {
 		defer wg.Done()